Control of emissions from fossil fuel combustions sources addresses a major environmental problem. The Environmental Protection Agency (EPA) through the Clean Air Act regulates the emissions from fossil fuel-fire power plants. Initial regulations were focused on oxides-of-nitrogen (NOx) and oxides-of-sulfur (SOx) emissions, but newer regulations will include provisions to control heavy metals (Hg, etc.) and carbon dioxide.
Gas streams from combustion processes are often scrubbed, i.e., contacted with water, to remove many of their contaminants. However, these scrubbing processes often produce hazardous waste streams that must be dealt with.
For the reasons stated above, and for other reasons stated below that will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternative methods and apparatus for treating combustion gas streams.